Heating and cooling apparatus

TLDR: In this paper, the authors present a closed loop heating and cooling system for a single, closed loop configuration for directly exchanging thermal energy with the earth for both heating, and a refrigerant storage device automatically supplies or accepts the change in quantity of the refrigerant required when the apparatus changes from either the heating or cooling mode to reverse mode.

Abstract: A heating and cooling method and apparatus for a single, closed loop configuration for directly exchanging thermal energy with the earth for both heating and cooling purposes. A refrigerant, which is pumped through the apparatus by a compressor, undergoes two phase transitions during each circuit through the loop. A subterranean heat exchanger has a pair of manifolds in flow communication with a plurality of substantially horizontally oriented tubes. Refrigerant flowing through the tubes has sufficient velocity to sweep lubricant oil, which has escaped from the compressor, along with it for return to the compressor. An expansion valving assembly automatically meters and regulates the flow rate and pressure of the refrigerant during both the heating mode and the cooling mode of the apparatus. A refrigerant storage device automatically supplies or accepts the change in quantity of the refrigerant required when the apparatus changes from either the heating or cooling mode to the reverse mode. A bypass mechanism anticipates the low pressure condition which arises at the compressor input during reversal or startup of the apparatus and provides multiple attempts to overcome inertial resistance corresponding thereto. A modified embodiment of the apparatus provides a non-phase-change heat exchanger flow communicating in tandem to remove a portion of the thermal energy for auxiliary thermodynamic purposes.